title: Tinnitus and normal hearing: a study on contralateral acoustic reflex.
abstract: OBJECTIVE
  The aim of this study was to evaluate the difference of the contralateral acoustic reflex (AR) threshold between adult subjects with hearing within clinically normal limits, with and without tinnitus.
  
  
  METHODS
  The study sample in this exploratory, descriptive, and comparative study comprised 40 female subjects who were evaluated: 20 had tinnitus and 20 formed the control group. The contralateral AR threshold was evaluated at the frequencies of 500, 1000, and 2000 Hz.
  
  
  RESULTS
  Elevated or absent AR thresholds were found only in subjects with complaints of tinnitus. At all frequencies and in either ear, the median AR threshold was higher in the group that complained of tinnitus (100.0 dB; range = 95.0–100.0 dB) compared with the control group (90.0 dB; range = 86.3–95.0 dB; p < .01). There was a statistically significant difference ( p < .05) in the group with tinnitus, in each of the frequencies studied and in both the right and left ear.
  
  
  CONCLUSIONS
  The results suggest that evaluation of the efferent system, through AR, could be an important tool for the differential diagnosis of tinnitus in patients whose hearing was within clinically normal limits.
authors.forename: Luciene da Cruz
authors.initials: Lda C
authors.lastname: Fernandes
authors.forename: Teresa Maria
authors.initials: TM
authors.lastname: Momensohn-Santos
authors.forename: Josiane Silva Martins
authors.initials: JS
authors.lastname: Carvalho
authors.forename: Fernando Luís de Queiroz
authors.initials: FL
authors.lastname: Carvalho
mesh_terms: D000293:Adolescent; D000328:Adult; D001309:Auditory Threshold / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D012022:Reflex, Acoustic / Q000502:physiology*; D014012:Tinnitus / Q000503:physiopathology*; D055815:Young Adult